With the growth of NWA, there's always the potential for a E-W interstate on US 412 west of I-49; any eastern extension across the Ozarks is a long shot at best. Of course, the major obstacle is ODOT; but since their more recent efforts are targeting both OKC and Tulsa, an upgraded route from the latter city to NWA might be something that would be considered with a modicum of local prodding -- especially since quite a bit of it is already constructed as a toll facility -- and that concept could be extended in both directions from the existing Cherokee facility. A "double-ended" corridor extending both east and west of Tulsa using the Cimarron pike wouldn't be out of the question either -- except for a single grade crossing, the western US 412 portion is already in service. But it would likely take actions from within AR to secure any Interstate designation for that corridor; it's unlikely any such initiative would emerge from any OK entity. But a facility along US 412 east of there would be unlikely to provide potential traffic levels to warrant even a 4-lane expressway much less a freeway. And connecting it east to the existing I-155 in MO's "bootheel" has been effectively usurped by the I-57 concept; it's improbable that an additional large freeway project in NE AR would see the light of day for at least several decades.